How to access and license sports betting odds?

June 22, 2010 9:24 AM

There are a number of websites that show the odds and (if I'm using the term right), the "lines" for various sporting events that physical and online casinos offer (linking would be spammy, but a quick search of "vegas odds" or some such thing will turn them up). My question is how do the site owners obtain the data from the casinos? I have to imagine the data is provided subject to a license agreement (and I would expect there to be some sort of schema to prevent sudden changes to the format of the data presented). How would one go about getting access to the feed of the odds and the payout ratios (?) from one or more casinos without getting rampaged by hoards of angry lawyers? Contacting the casinos has, unsurprisingly, proven fruitless given the difficulty explaining what I'm looking for to a non-technical support representative ("So you want to know how to gamble online?"). NB: I've never bet on sports, so apologies if my lingo is off. I appreciate any help and guidance!
posted by Imhotep is Invisible to computers & internet (8 answers total)

The various online casinos actively encourage people to post their odds. They provide technical support for linking their live odds feeds on your website. In sportsbetting parlance, anyone who does this sort of advertising for an online casino is an affiliate. If someone clicks on the odds on an affiliate website and joins an online casino, the affiliate gets a kickback.

As far as I know, the brick and mortar casinos do not provide interactive data feeds and if anyone posts the odds for the various casinos, they would have to collect that data by hand. I don't live in Vegas, so I've never really had a need to check the brick and mortar odds. For a time, I experimented with doing arbitrage where one online sportsbook had odds that were different than another and I could bet both sides for a guaranteed profit. It took a lot of time and only returned small rewards, so I got bored with it. I know people who do it a lot, usually in conjunction with working the cash incentive offers to get you to join a new gambling site. If you are disciplined and have no better options, you can make a modest living doing this.
posted by Lame_username at 10:29 AM on June 22, 2010

Lame_username: regarding your arbitrage experiment, it's absolutely fascinating, and I imagine the cat-and-mouse that I expect would take place between arbitrageurs and the online casinos would be equally interesting!

I'm surprised that the brick-and-mortar casinos don't post their odds, unless they're consistently inferior to those offered by the online casinos. I realized early on that anything having to do with gaming or betting would most likely be wildly intricate and hard to understand, although I would have thought there would have been at least some transparency at least at this level.
posted by Imhotep is Invisible at 10:37 AM on June 22, 2010

I think you may have it somewhat backwards. My understanding is that many casinos work with companies that provide them with odds on sporting events.

Take a look at Las Vegas Sports Consultants.

Here's an article from the WSJ about the company. It's probably paywalled, so here's an interesting excerpt:

In 2003, Mr. White and two partners bought LVSC. On the second-floor of an office park behind the Las Vegas airport, its nine oddsmakers crank out betting lines for every major college and professional sport. During the busy November sports season, they put out well over 500 lines a week on major events -- not counting golf, tennis, Nascar, soccer and boxing. By Mr. White's estimate, the company now provides betting lines to about 90% of Las Vegas's casinos.

Also, I believe the sportsbooks at the major Vegas casinos are not very profitable. They're there to draw in people, who are likely to play slot machines or table games.
posted by mullacc at 11:07 AM on June 22, 2010

mullacc: but aren't there two components: the actual odds ("Team A will beat Team B by X points") and then the payout ("X dollars for Y dollars wagered")? So even if almost all sportsbooks report the same odds (which seems, well, odd to begin with), wouldn't there still be variance based on what payouts were offered?

Amusingly, I used to live in Vegas, but I could never wrap my head around gaming. It's a shame that I don't know anyone there any more...
posted by Imhotep is Invisible at 11:16 AM on June 22, 2010

You are right, you don't really get it. ;)

Most sports like football have two different kinds of wagers, the point spread and the money line. For a particular game between say the Saints and the Falcons, the point spread might be Falcons +3.5 points. This means that if you choose to bet on the Falcons, you will win if they lose by 3 points or less (or if they win outright). If you bet on the Saints, they must win by 4 points or more or you will lose. Basically all such bets either live or online pay -110, which means you have to bet $110 to win $100. Once in a while, the payouts will move a bit, usually when a point spread gets stuck on 3 points. You will see -115 or -105 in those cases. The reason for this is that a win by exactly 3 points is very common, so changing the spread to +3.5 or +2.5 will attract a lot of betters to the other side. But as a rule, the payouts for "spread" bets is usually -110.

The "money line" is a bet that one team will win "straight-up" which is to say that they will win in the NFL definition of the term. These bets will pay at odds related to the bookmaker's estimate of the likelihood of each team winning. In our hypothetical example, the Falcons might be +150, meaning you would win $150 for every $100 wagered and the Saints might be -160, meaning you would have to wager $160 to win $100. There is a mathematical relationship between the value of the money line and the point spread, but that is an esoteric concept.

As a rule, the sports books move in concert. If one book is giving you the Saints -3 and another book is giving you the Falcons +3.5, you might find it worthwhile to bet a lot at each book, because if the Saints end up winning by exactly 3, you will push the one bet and win the other. It isn't exactly a freeroll, because if you bet $100 on each side, you will lose $10 any time the game doesn't end on exactly 3 points and win $90 when it does. But if you know that NFL games like this end on exactly 3 points more than 10% of the time, you might take it. As the gaps get larger between one book and another, large sums of money will be attracted to outlying book. If I want to bet the Falcons anyhow, it would obviously benefit me to take the 3.5 points instead of the 3 and the book that is out of line will attract a lot of Falcons money.

There are some books (Pinnacle was famous for this back in the day before Congress scared them out of taking bets from Americans) that intentionally establish a line that stands out from the other books. My understanding is that they thought they were smarter than the other books and were perfectly happy to take a lot of unbalanced action. After a while, it seemed that the other books would adjust within minutes of Pinny moving their line. My arbitrage bets were almost always between Pinnacle and another book. At one point I analyzed the results of these bets and found that I would lose on Pinnacle and win on the other book 61% of the time. If this same thing was true of other arbitrage bettors, Pinnacle was making a fortune off the other books.

I'm probably pretty far afield of your original question, so I'll stop rambling.
posted by Lame_username at 12:10 PM on June 22, 2010 [1 favorite]

Er, no...you're getting some terms confused. What you call a "payout" is usually called the odds and what you call the "odds" is the spread. Not every type of bet has a spread, but every bet has odds, even if the odds are 1:1 (or +100 in moneyline terms).

Casinos (or the odds-making services) minimize arbitrage opportunities, whether it's between types of bets or location of the sportsbook. But remember that the house isn't really playing for its own account. The house is trying to set odds so that the amount of money bet on each side of a particular bet balance out. That way the house isn't risking its own capital, but just earning a fee for providing a service. This creates an incentive for casinos (online or physical) to share information and keep odds consistent.

There are also professional gamblers that enforce this by monitoring all sorts of sportsbooks and taking advantage of arbitrage opportunities. It's similar to a Wall Street trading desk. When the casinos see money flowing into one side of a bet more than the other, they adjust. The professional gambling operations are in cahoots with the casinos--the gamblers get a chance to make favorable bets and the casinos have a chance to adjust their odds before the unwashed masses figure it out.

On preview: I'm mostly saying the same thing as Lame_username, so I'll stop too. :)
posted by mullacc at 12:21 PM on June 22, 2010

aren't there two components: the actual odds ("Team A will beat Team B by X points") and then the payout ("X dollars for Y dollars wagered")? So even if almost all sportsbooks report the same odds (which seems, well, odd to begin with), wouldn't there still be variance based on what payouts were offered?


On a individual bet odds are payout. Bookmakers work the other way round : odds are determined by payout. Bookmakers work to a percentage known as an 'overround'. If the overround is 110% this means for every $100 they pay out they will take in $110 (at least theoretically). 'Making a book' means adjusting the odds, on different outcomes , to try and ensure this happens. Wikipedia's page on the mathematics of bookmaking has the details but basically it works like this. You can convert odds into a percentage, so if I offer 4 to 1 (400 in US terms) on team A winning this corresponds to a relative probability of 20%. So when I calculate the odds on the other outcomes (lose, draw) I need to ensure the percentages of all three added together is equal to my overround (e.g. 110%). From my experience working for a bookmaker (doing IT not betting) the percentage was fairly consistent across the industry, but online gambling, and bet exchanges, in particular, are exerting a downward pressure
(bet exchanges work at 100% but take a commission).

It is worth knowing that odds typically reflect the amount of risk to the bookmaker as determined by the amount of money wagered. In practice making a book relies on balanced wagers but you don't know how much money is going to be placed on each outcome. One of the ways bookmakers control for this is by adjusting the odds according to the amount of wagers. So if larger amounts are being staked on an outcome the bookmaker will adjust the odds for that particular downwards to compensate (they also hedge their bets by placing bets with other bookmakers, especially for large individual bets). They can also raise the odds on the other bets in proportion to attract more wagers.

You can see this in action in the UK horse racing -- off-course and online bookmakers take their cues form the on-course bookmakers. These form a kind of live market in risk: they are constantly adjusting their prices according to how much money they take, and the odds other book makers are offering. This goes on right up until the start of the race. In fact it is common to take bets on SP(starting price) where you don't know what the odds will be but rather accept the average of on-course bookmaker prices at the start of the race.

The place I worked was an online bookmaker and we had lots of specialist satellite feeds that reported not just sporting events but odds offered and people kept a close eye on what other bookmakers were offering. I can't remember exactly how it worked but there were lots of sources of info, newspapers carrying the prices form the big bookmakers etc. Bookmakers will also be phoning up other bookmakers to make hedges so they also learn prices this way.
posted by tallus at 2:09 PM on June 22, 2010

Not to "overmark" for best answer, but the answers provided are wildly helpful. Thanks all!
posted by Imhotep is Invisible at 11:03 AM on June 23, 2010